Dungeons & Dragons
The original Dungeons & Dragons (D&D) game created a three-alignment system of law, neutrality and chaos. In Advanced Dungeons & Dragons, this became a two-dimensional grid, one axis of which measures a "moral" continuum between good and evil, and the other "ethical" between law and chaos, with a middle ground of "neutrality" on both axes for those who are indifferent, committed to balance, or lacking the capacity to judge. This system was retained more or less unchanged through the 2nd and 3rd editions of the game. By combining the two axes, any given character has one of nine possible alignments:
Neutral in this scheme can be one of two versions: Neutral, those who have no interest in (or no ability to care about) the choice; or "True Neutral", meaning those who not only actively remain neutral but believe it is necessary to enforce the balance of the world on others, and would act in any required fashion to bring about that balance.
In the 4th edition of the game, the alignment system was simplified, reducing the number of alignments to five. The 5th edition of D&D returned to the previous two-axis system.
Warhammer Fantasy Roleplay originally used a linear five-place system: Law – Good – Neutral – Evil – Chaos. In changes of alignment (for whatever reason) a character moved one place along to the next position (e.g.: a neutral character could move to good or evil but not to chaotic).
In practise, the system was used to regulate reactions between characters of different alignments.
In the newer edition, the concept of alignment (and the presence of Law as the antithesis of Chaos) has been discarded, with more emphasis on the personalities and unique natures of characters, rather than a linear alignment system.
Palladium uses a system where alignments are described in detailed terms of how a character acts in a certain situation: whether they will lie, how much force they will use against innocents, how they view the law, and so on. The alignments are organized into three broad categories: Good, Selfish, and Evil. The seven core alignments are Principled (Good), Scrupulous (Good), Unprincipled (Selfish), Anarchist (Selfish), Aberrant (Evil), Miscreant (Evil), and Diabolic (Evil). An eighth alignment, Taoist, was introduced in the Mystic China supplement, but has not seen wide use.
Each category contains answers to a set of questions on moral behaviours. For example, given the question "Would you keep a wallet full of cash you found?", most selfish or evil alignments would keep it, while most good alignments would seek to return the wallet to its owner. The categories are not organized into a pattern like Dungeons & Dragons. The system specifically does not include any sort of "neutral" alignment on the grounds that a neutral point of view is antithetical to the active role heroes and villains should play in a story.
The alignments of the Wizards of the Coast Star Wars Roleplaying Game are limited to Light Side and Dark Side, though there are variations within these.
In the older West End Games version of the game, behaviour is controlled with Force points which indicate one use of it per point. When using The Force for evil deeds, the character gains a Dark Side point which can accumulate and put the character at risk of being turned to the Dark Side, at which point the player loses control of their character. By contrast, heroic deeds using The Force allow the player to remove the point. In addition, using The Force at a dramatically appropriate moment, such as Luke Skywalker firing his proton torpedoes in the Death Star's exhaust port in the Battle of Yavin, can have a multiplier effect on points.